const landDom = document.querySelector(".land");
const landStyle = getComputedStyle(landDom);
const landWidth = parseFloat(landStyle.width);
const landHeight = parseFloat(landStyle.height);
const landtop = parseFloat(landStyle.top); 

class Land extends dad {
    constructor(speed){
        super( landWidth, landHeight, 0,landtop,speed,0,landDom);
    }

    onMove(){
        if(this.left<=-landWidth / 2){
            this.left = 0;
        }
    }

}
